sendme: Move code to the new files sendme.{c|h}

Take apart the SENDME cell specific code and put it in sendme.{c|h}. This is
part of prop289 that implements authenticated SENDMEs.

Creating those new files allow for the already huge relay.c to not grow in LOC
and makes it easier to handle and test the SENDME cells in an isolated way.

This commit only moves code. No behavior change.

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/core/include.am

@@ -52,6 +52,7 @@ LIBTOR_APP_A_SOURCES = 				\
 	src/core/or/scheduler.c			\
 	src/core/or/scheduler_kist.c		\
 	src/core/or/scheduler_vanilla.c		\
+	src/core/or/sendme.c			\
 	src/core/or/status.c			\
 	src/core/or/versions.c			\
 	src/core/proto/proto_cell.c		\
@@ -272,6 +273,7 @@ noinst_HEADERS +=					\
 	src/core/or/relay.h				\
 	src/core/or/relay_crypto_st.h			\
 	src/core/or/scheduler.h				\
+	src/core/or/sendme.h				\
 	src/core/or/server_port_cfg_st.h		\
 	src/core/or/socks_request_st.h			\
 	src/core/or/status.h				\

src/core/or/connection_edge.c

@@ -73,6 +73,7 @@
 #include "core/or/policies.h"
 #include "core/or/reasons.h"
 #include "core/or/relay.h"
+#include "core/or/sendme.h"
 #include "core/proto/proto_http.h"
 #include "core/proto/proto_socks.h"
 #include "feature/client/addressmap.h"
@@ -767,7 +768,7 @@ connection_edge_flushed_some(edge_connection_t *conn)
 
       /* falls through. */
     case EXIT_CONN_STATE_OPEN:
-      connection_edge_consider_sending_sendme(conn);
+      sendme_connection_edge_consider_sending(conn);
       break;
   }
   return 0;
@@ -791,7 +792,7 @@ connection_edge_finished_flushing(edge_connection_t *conn)
   switch (conn->base_.state) {
     case AP_CONN_STATE_OPEN:
     case EXIT_CONN_STATE_OPEN:
-      connection_edge_consider_sending_sendme(conn);
+      sendme_connection_edge_consider_sending(conn);
       return 0;
     case AP_CONN_STATE_SOCKS_WAIT:
     case AP_CONN_STATE_NATD_WAIT:

src/core/or/relay.c

@@ -93,13 +93,12 @@
 #include "core/or/origin_circuit_st.h"
 #include "feature/nodelist/routerinfo_st.h"
 #include "core/or/socks_request_st.h"
+#include "core/or/sendme.h"
 
 static edge_connection_t *relay_lookup_conn(circuit_t *circ, cell_t *cell,
                                             cell_direction_t cell_direction,
                                             crypt_path_t *layer_hint);
 
-static void circuit_consider_sending_sendme(circuit_t *circ,
-                                            crypt_path_t *layer_hint);
 static void circuit_resume_edge_reading(circuit_t *circ,
                                         crypt_path_t *layer_hint);
 static int circuit_resume_edge_reading_helper(edge_connection_t *conn,
@@ -1564,7 +1563,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
       log_debug(domain,"circ deliver_window now %d.", layer_hint ?
                 layer_hint->deliver_window : circ->deliver_window);
 
-      circuit_consider_sending_sendme(circ, layer_hint);
+      sendme_circuit_consider_sending(circ, layer_hint);
 
       if (rh.stream_id == 0) {
         log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL, "Relay data cell with zero "
@@ -1615,7 +1614,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
         /* Only send a SENDME if we're not getting optimistic data; otherwise
          * a SENDME could arrive before the CONNECTED.
          */
-        connection_edge_consider_sending_sendme(conn);
+        sendme_connection_edge_consider_sending(conn);
       }
 
       return 0;
@@ -1869,7 +1868,7 @@ connection_edge_process_relay_cell(cell_t *cell, circuit_t *circ,
       /* Don't allow the other endpoint to request more than our maximum
        * (i.e. initial) stream SENDME window worth of data. Well-behaved
        * stock clients will not request more than this max (as per the check
-       * in the while loop of connection_edge_consider_sending_sendme()).
+       * in the while loop of sendme_connection_edge_consider_sending()).
        */
       if (conn->package_window + STREAMWINDOW_INCREMENT >
           STREAMWINDOW_START_MAX) {
@@ -2117,42 +2116,6 @@ connection_edge_package_raw_inbuf(edge_connection_t *conn, int package_partial,
   goto repeat_connection_edge_package_raw_inbuf;
 }
 
-/** Called when we've just received a relay data cell, when
- * we've just finished flushing all bytes to stream <b>conn</b>,
- * or when we've flushed *some* bytes to the stream <b>conn</b>.
- *
- * If conn->outbuf is not too full, and our deliver window is
- * low, send back a suitable number of stream-level sendme cells.
- */
-void
-connection_edge_consider_sending_sendme(edge_connection_t *conn)
-{
-  circuit_t *circ;
-
-  if (connection_outbuf_too_full(TO_CONN(conn)))
-    return;
-
-  circ = circuit_get_by_edge_conn(conn);
-  if (!circ) {
-    /* this can legitimately happen if the destroy has already
-     * arrived and torn down the circuit */
-    log_info(LD_APP,"No circuit associated with conn. Skipping.");
-    return;
-  }
-
-  while (conn->deliver_window <= STREAMWINDOW_START - STREAMWINDOW_INCREMENT) {
-    log_debug(conn->base_.type == CONN_TYPE_AP ?LD_APP:LD_EXIT,
-              "Outbuf %d, Queuing stream sendme.",
-              (int)conn->base_.outbuf_flushlen);
-    conn->deliver_window += STREAMWINDOW_INCREMENT;
-    if (connection_edge_send_command(conn, RELAY_COMMAND_SENDME,
-                                     NULL, 0) < 0) {
-      log_warn(LD_APP,"connection_edge_send_command failed. Skipping.");
-      return; /* the circuit's closed, don't continue */
-    }
-  }
-}
-
 /** The circuit <b>circ</b> has received a circuit-level sendme
  * (on hop <b>layer_hint</b>, if we're the OP). Go through all the
  * attached streams and let them resume reading and packaging, if
@@ -2369,33 +2332,6 @@ circuit_consider_stop_edge_reading(circuit_t *circ, crypt_path_t *layer_hint)
   return 0;
 }
 
-/** Check if the deliver_window for circuit <b>circ</b> (at hop
- * <b>layer_hint</b> if it's defined) is low enough that we should
- * send a circuit-level sendme back down the circuit. If so, send
- * enough sendmes that the window would be overfull if we sent any
- * more.
- */
-static void
-circuit_consider_sending_sendme(circuit_t *circ, crypt_path_t *layer_hint)
-{
-//  log_fn(LOG_INFO,"Considering: layer_hint is %s",
-//         layer_hint ? "defined" : "null");
-  while ((layer_hint ? layer_hint->deliver_window : circ->deliver_window) <=
-          CIRCWINDOW_START - CIRCWINDOW_INCREMENT) {
-    log_debug(LD_CIRC,"Queuing circuit sendme.");
-    if (layer_hint)
-      layer_hint->deliver_window += CIRCWINDOW_INCREMENT;
-    else
-      circ->deliver_window += CIRCWINDOW_INCREMENT;
-    if (relay_send_command_from_edge(0, circ, RELAY_COMMAND_SENDME,
-                                     NULL, 0, layer_hint) < 0) {
-      log_warn(LD_CIRC,
-               "relay_send_command_from_edge failed. Circuit's closed.");
-      return; /* the circuit's closed, don't continue */
-    }
-  }
-}
-
 /** The total number of cells we have allocated. */
 static size_t total_cells_allocated = 0;
 

src/core/or/sendme.c

@@ -0,0 +1,76 @@
+/* Copyright (c) 2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file sendme.c
+ * \brief Code that is related to SENDME cells both in terms of
+ *        creating/parsing cells and handling the content.
+ */
+
+#include "core/or/or.h"
+
+#include "core/mainloop/connection.h"
+#include "core/or/circuitlist.h"
+#include "core/or/relay.h"
+#include "core/or/sendme.h"
+
+/** Called when we've just received a relay data cell, when
+ * we've just finished flushing all bytes to stream <b>conn</b>,
+ * or when we've flushed *some* bytes to the stream <b>conn</b>.
+ *
+ * If conn->outbuf is not too full, and our deliver window is
+ * low, send back a suitable number of stream-level sendme cells.
+ */
+void
+sendme_connection_edge_consider_sending(edge_connection_t *conn)
+{
+  circuit_t *circ;
+
+  if (connection_outbuf_too_full(TO_CONN(conn)))
+    return;
+
+  circ = circuit_get_by_edge_conn(conn);
+  if (!circ) {
+    /* this can legitimately happen if the destroy has already
+     * arrived and torn down the circuit */
+    log_info(LD_APP,"No circuit associated with conn. Skipping.");
+    return;
+  }
+
+  while (conn->deliver_window <= STREAMWINDOW_START - STREAMWINDOW_INCREMENT) {
+    log_debug(conn->base_.type == CONN_TYPE_AP ?LD_APP:LD_EXIT,
+              "Outbuf %d, Queuing stream sendme.",
+              (int)conn->base_.outbuf_flushlen);
+    conn->deliver_window += STREAMWINDOW_INCREMENT;
+    if (connection_edge_send_command(conn, RELAY_COMMAND_SENDME,
+                                     NULL, 0) < 0) {
+      log_warn(LD_APP,"connection_edge_send_command failed. Skipping.");
+      return; /* the circuit's closed, don't continue */
+    }
+  }
+}
+
+/** Check if the deliver_window for circuit <b>circ</b> (at hop
+ * <b>layer_hint</b> if it's defined) is low enough that we should
+ * send a circuit-level sendme back down the circuit. If so, send
+ * enough sendmes that the window would be overfull if we sent any
+ * more.
+ */
+void
+sendme_circuit_consider_sending(circuit_t *circ, crypt_path_t *layer_hint)
+{
+  while ((layer_hint ? layer_hint->deliver_window : circ->deliver_window) <=
+          CIRCWINDOW_START - CIRCWINDOW_INCREMENT) {
+    log_debug(LD_CIRC,"Queuing circuit sendme.");
+    if (layer_hint)
+      layer_hint->deliver_window += CIRCWINDOW_INCREMENT;
+    else
+      circ->deliver_window += CIRCWINDOW_INCREMENT;
+    if (relay_send_command_from_edge(0, circ, RELAY_COMMAND_SENDME,
+                                     NULL, 0, layer_hint) < 0) {
+      log_warn(LD_CIRC,
+               "relay_send_command_from_edge failed. Circuit's closed.");
+      return; /* the circuit's closed, don't continue */
+    }
+  }
+}

src/core/or/sendme.h

@@ -0,0 +1,20 @@
+/* Copyright (c) 2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file sendme.h
+ * \brief Header file for sendme.c.
+ **/
+
+#ifndef TOR_SENDME_H
+#define TOR_SENDME_H
+
+#include "core/or/edge_connection_st.h"
+#include "core/or/crypt_path_st.h"
+#include "core/or/circuit_st.h"
+
+void sendme_connection_edge_consider_sending(edge_connection_t *edge_conn);
+void sendme_circuit_consider_sending(circuit_t *circ,
+                                     crypt_path_t *layer_hint);
+
+#endif /* !defined(TOR_SENDME_H) */